The use of spray drying to produce powders from fluid feed stocks is well known, with applications ranging from powdered milk to bulk chemicals and pharmaceuticals. A typical spray-drying apparatus comprises a drying chamber, an atomizing means for atomizing a solvent-containing feed into the drying chamber, a drying gas that flows into the drying chamber to remove solvent from the atomized solvent-containing feed, and a product collection means located downstream of the drying chamber.